Gait Recognition Using WiFi Signals Wei Wang Alex X.Liu Muhammad Shahzad Nanjing University Michigan State University North Carolina State University Nanjing University GAN STATE NANJING UNIVERSITY 1902 Founded 1855
1/96 Gait Recognition Using WiFi Signals Wei Wang Alex X. Liu Muhammad Shahzad Nanjing University Michigan State University North Carolina State University Nanjing University
Gait Based Human Authentication ldentification Human Authentication Problem Statement:Are you Trump or not? Why need gait based human authentication? Multi-factor human authentication Human ldentification Problem Statement:Which one of the following people are you:Trump or Hillary? Why need gait based human identification? ·Customization 3/96
3/96 Gait Based Human Authentication & Identification § Human Authentication – Problem Statement: Are you Trump or not? – Why need gait based human authentication? • Multi-factor human authentication § Human Identification – Problem Statement: Which one of the following people are you: Trump or Hillary? – Why need gait based human identification? • Customization
Gait Based Human Authentication ldentification Why possible? Individually unique gait patterns -What have been done? Video camera ·Cannot work in dark ·Privacy concern Wearble sensors ·Inconvenient Floor sensors ·Expensive What do we propose? WiFi signals 4/96
4/96 Gait Based Human Authentication & Identification § Why possible? – Individually unique gait patterns § What have been done? – Video camera • Cannot work in dark • Privacy concern – Wearble sensors • Inconvenient – Floor sensors • Expensive § What do we propose? – WiFi signals
WiFiU:Gait Based Human Authentication Recognition Using WiFi Signals Using commercial off the shelf devices Woks in dark Privacy friendly NetGEAR JR6100 Lenovo Thinkpad X200 5/96
5/96 WiFiU: Gait Based Human Authentication & Recognition Using WiFi Signals § Using commercial off the shelf devices § Woks in dark § Privacy friendly NetGEAR JR6100 Lenovo Thinkpad X200
Key Insight Human body reflects wireless signals WiFi signal WiFi router WiFi signal reflection Laptop Signal analysis Chanel State Information (CSI)has huge amount of useful information about environmental changes 2,500 samples per second Complex valued samples with 8 bit accuracy On 30 subcarriers for each antenna pair ■ So,commercial WiFi devices can act as Doppler Radars to measure human activities 6/96
6/96 Key Insight § Human body reflects wireless signals § Chanel State Information (CSI) has huge amount of useful information about environmental changes – 2,500 samples per second – Complex valued samples with 8 bit accuracy – On 30 subcarriers for each antenna pair § So, commercial WiFi devices can act as Doppler Radars to measure human activities Signal analysis WiFi router Laptop WiFi signal reflection WiFi signal